Handle and trigger construction

ABSTRACT

A portable tool including a housing having a rotary pneumatic motor disposed therein and coupled to a tool spindle. Compressed air is delivered to the motor by conduit means which includes passage means in a handle dependent from the housing. A throttle valve is disposed within the handle and is controlled by a trigger pivoted upon the handle. The trigger and handle are provided with novel adjustable stop means to limit trigger movement.

United States Patent Sauerwein et al.

[15] 3,666,027 [451 May 30, 1972 [54] HANDLE AND TRIGGER CONSTRUCTION[72] Inventors: William D. Sauerwein, Joppa; Robert A.

Meloni, Baltimore; Harvey J. Walter, Joppatown, all of Md.

The Bhick and Decker Manufacturing Company, Towson, Md.

[22] Filed: Aug. 1, 1970 [21] Appl. No.: 65,954

[73] Assignee:

52] U.S.Cl ..173/169,173/l70 51] lm. Cl ..B23b45/04 5s FieldofSeai-ch..l73/l69,l63,l70,l8

[56] References Cited UNITED STATES PATENTS Maurer ..173/170 X 2,898,8938/1959 Rohrer et a1 ..173/l70 X 3,037,740 6/ 1962 Sheps et a1. 3,352,36811/1967 Maffey .1 173/169 Primary Examiner-David H. BrownAttorney-Leonard Bloom, Joseph R. Slotnik and Edward D. Murphy 57ABSTRACT A portable tool including a housing having a rotary pneumaticmotor disposed therein and coupled to a tool spindle. Compressed air isdelivered to the motor by conduit means which includes passage means ina handle dependent from the housing. A throttle valve is disposed withinthe handle and is controlled by a trigger pivoted upon the handle. Thetrigger and handle are provided with novel adjustable stop means tolimit trigger movement.

SCIainsADrawingFigures Patented May 30, 1972 3,666,027

INVENTORS WILLIAM D. SAUERWEIN ROBERT A. MELON! ATTRNEY HANDLE ANDTRIGGER CONSTRUCTION SUMMARY OF THE INVENTION The present invention isdirected to a novel adjustable trigger construction for a variablespeed, portable tool or the like. The trigger is pivoted upon, forexample, a tool handle to operate a throttle valve, electrical orelectronic speed control, or the like, and includes adjustable meansintegrated therewith and cooperable with means rigid with the handle tovary the extent to which the trigger can pivot and therefore the speedof the tool. The adjustable means is adapted for easy, manualadjustment, includes means for retaining it in incrementally adjustedpositions, and is constructed so that the tool will operate even if theadjustable means is removed or fails. Furthermore, the adjustable meansis safe, compact and convenient, involves a minimum of parts andexpense, and presents a neat and aesthetically pleasing appearance.

Main objects of the present invention are to provide a novel pivotal,adjustable trigger construction for a variable speed power tool or thelike, which construction is compact and is integrated with the triggerand its mount, and is quickly and easily manually adjustable while beingretained in incrementally adjusted positions.

Further important objects are to provide a novel trigger construction ofthe above character which will function in the absence of or uponfailure of the adjustment construction, which includes a minimum ofseparate parts, and wherein most of these parts are concealed or out ofthe way thereby presenting a neat and aesthetically pleasing appearance.

Additional important objects are to provide a novel trigger constructionof the above character which is relatively inexpensive to manufacture,rugged in construction, and safe and reliable in use.

Other objects and advantages will become more apparent from aconsideration of the detailed description to follow taken in conjunctionwith the drawings annexed thereto.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional viewillustrating a portable pneumatic tool embodying the present inventionand showing the trigger construction in one adjusted position;

FIG. 2 is a view of a portion of FIG. 1 and showing the triggerconstruction in another adjusted position;

FIG. 3 is an enlarged sectional view of the structure of FIG. 1 takenalong the line 3-3 thereof; and

FIG. 4 is an enlarged sectional view of FIG. 2 taken along the line 4-4thereof.

BROAD STATEMENT OF THE INVENTION Broadly described, the presentinvention relates to a portable tool comprising a housing, a variablespeed motor in said housing and adapted to be connected to a powersource, control means for varying the speed of said motor, a triggerpivoted on said housing and interconnected with said control means andmovable in a first direction to turn said motor off and in a seconddirection to turn said motor on, said trigger having an outer portionadapted for finger engagement during operation of said tool and an innerportion generally inaccessible to the fingers of an operator during tooloperation, engageable abutment means rigid with said housing and triggerto limit movement of said trigger in said second direction, means onsaid trigger at the inner portion thereof for adjusting said abutmentmeans relative thereto whereby to adjust the range of pivotal movementof said trigger in said second direction and correspondingly the speedof said motor.

DETAILED DESCRIPTION Referring now more specifically to the drawings,the present invention is seen embodied in a pneumatic impact wrenchgenerally indicated at 11 in FIG. 1. However, it is to be understoodthat this tool is for purposes of illustration only.

With this in mind, the wrench 11 includes a housing comprising a motorhousing 13, a clutch housing 15, a rear cover 16, and a handle 17secured together in suitable fashion. A rotary pneumatic motor 18 isdisposed in the motor housing 13 and includes a rotor 19 having fore andaft stub shafts 21, 23 rotatably supported by bearings 25, 27 in endplates 29, 31. The rotor 19 carries a plurality of radially disposedvanes 33 adapted to slidably engage the inner wall of a cylinder liner35 and trapped endwise between the end plates 29, 31.

The stub shaft 21 is splined to a cam driver 37 which is coupled to adog 39. A clutch pin 41 connects the dog 39 and a clutch body 43, andthe dog 39 is adapted to engage a jaw 45 formed on a clutch shank 46.The forward end of the shank 46 forms a tool spindle 47 to which asuitable tool bit, e.g. a wrench socket, can be fixed and is supportedwithin the housing by a bushing 49. The dog 39 is adapted to engage andconstantly drive the shank 46 at low torque levels and intermittentlyengage or impact against the shank 46 at higher torque levels.

Pressurized air is delivered to the tool 11 from a source through aconduit (not shown) fastened to a coupling 51 threaded into a valvecavity 53 in the handle 17. A valve member 57 is positioned in thecavity 53 and is normally biased by a compression spring 59 into seatedrelation with a valve ring 55. The valve member 57 has a stem 61extending through an opening 63 in the ring 55 and is slidably receivedin an opening 65 in the handle 17.

When the valve 57 is unseated from the ring 55, pressurized air isdelivered to passage 67 and port 69 in the handle 17 and a reversingvalve sleeve 71, respectively. In the position of the parts shown inFIG. 1, this air then passes out through a port 73 in sleeve 71, throughpassages (not shown) in the housing 13 and rear cover 16, and then tothe motor 18. Air is exhausted from the motor 18 through ports 75, 77 inthe liner 35, ports 79, 81 in housing 13 and sleeve 71, and out toatmosphere.

When it is desired to reverse operation of the motor, a spool 83positioned in the sleeve 71 is pushed rearwardly or toward the right, asseen in FIG. 1. Now, pressurized fluid flows from passage 67 and 69 outthrough port 85, and to motor 18 through other passages (not shown) inthe housing 13 and rear cover 16. Air is now exhausted from motor 18through ports 75, 77 ports 87, 89 in housing 13 and sleeve 71, and thento atmosphere. Desirably, detent means (not shown) retains the spool 83in these positions.

A trigger, generally indicated at 91 in FIGS. 1 and 2, is provided onthe handle 17 for actuation of the throttle valve. As shown, the triggerincludes a body 93 set partially within a pocket 94 in the handle 17 andpivoted at its lower end thereon by a pin 95. The body 93 has an innerportion which is inaccessible to the operators fingers during normaltool operation and formed with a recess 97 which defines first andsecond abutment surfaces 99, 101. A projection 103 formed integral withthe handle 17 and located within the pocket 94 is receivable in therecess 97 and defines first and second abutment surfaces 105, 107adapted to engage the abutment surfaces 99, 101 and limit pivotalmovement of the trigger body 93 in both directions.

The trigger body 93 has a surface 109 adapted to engage the end of thevalve stem 61. The body 93 also has an outer portion including aconcavely shaped upper portion 111 which accommodates one or morefingers of the operator when his hand is on the handle 17. Thus, withhis hand so positioned, the operator can easily pivot the trigger body93 in a clockwise direction, as seen in FIGS. 1 and 2, whereby to movethe valve stem 61 downwardly and unseat the valve body 57 from the ring55. This, in turn, allows pressurized air to pass into the motor 18 androtates the rotor 19 and the shank 46 and spindle 47. Clockwise pivotalmovement of the trigger body 93 is limited by engagement of the surfaces99, which, in turn, limits the extent to which the valve 57 can moveaway from the ring 55. When the trigger body 93 is released, the spring59 moves the valve body 57 back into seated relationship with the ring55 (to shut off the tool) and the valve stem 61 pivots the trigger body93 in a counterclockwise direction. Engagement between surfaces 101, 107limits pivotal movement of the body 93 in this direction and preventsthe body 93 from coming completely out of the pocket 94.

It is desirable that means be provided to adjust the throttling actionof the valve body 57. To this end, the effective position of theabutment surface 99 relative to the abutment surface 105 is adjusted sothat the extent to which the trigger body 93 can pivot in a clockwisedirection is correspondingly adjusted. This is achieved by a screw 113which is threaded into the body 93 and having an end 115 adapted toextend beyond the surface 99.

FIG. 1 illustrates the screw 113 withdrawn so that its surface 115 doesnot protrude from the surface 99. In this position, full pivotalmovement of the trigger 93 is allowed and the valve 57 can open fully.FIG. 2, on the other hand, shows the screw 113 adjusted so that itssurface 115 extends beyond the surface 99. Now, the screw surface 115engages the surface 105 before surface 99 does and correspondinglylimits allowed pivotal movement of the trigger 93 and the extent towhich the valve 57 can open.

The screw 1 13 is provided with a knurled head 117 which is outside thetrigger body 93 but is behind the finger portion 111. This allows theoperator to easily adjust the screw 113 while partially concealing itand rendering it inaccessible during tool operation. However, to resistinadvertent or accidental movement of the screw 113, a detent comprisinga ball 119 and spring 121, is set into a pocket 123 in the trigger body93, and cooperatively engages the knurled head 117, as seen in thedrawings. It will be appreciated, however, the screw 113 can be fingerturned against the holding force of the ball 119 and spring 121.

It will be appreciated that the handle 17 (which generally is castmetal) simply is formed with the pocket 94 and the integral projection103. The trigger body 93, on the other hand, is a relatively small andreplaceable element and can be molded using a suitable plastic. Thescrew 113 is threaded directly into the body 93 (rather than the handle17) and the ball and spring 119, 121, also located therein so that thistrigger assembly can be packaged and assembled to handle 17 as aseparate unit. Thus, this trigger construction described achievesmaximum efficiency, convenience, and reliability, with a minimum ofcost, and, in addition, by the concealed ball, detent and screw,presents a neat and aesthetically pleasing appearance devoid ofunsightly or unattractive parts.

By the foregoing there has been disclosed a novel trigger constructioncalculated to fulfill the inventive objects set forth, and while apreferred embodiment of the invention has been illustrated and describedin detail, various additions, substitutions, modifications, andomissions may be made thereto without departing from the spirit of theinvention.

We claim:

1. A portable tool comprising a housing, a variable speed motor in saidhousing and adapted to be connected to a power source, control means forvarying the speed of said motor, a trigger pivoted on said housing andinterconnected with said control means, and movable in a first directionto turn said motor off and in a second direction to turn said motor on,"said trigger having an outer portion adapted for finger engagementduring operation of said tool and an inner portion generallyinaccessible to the fingers of an operator during tool operation,engageable abutment means rigid with said housing and trigger to limitmovement of said trigger in said second direction, means on said triggerat the inner portion thereof for adjusting said abutment means relativethereto whereby to adjust the range of pivotal movement of said triggerin said second direction and correspondingly the speed of said motor.

2. A tool as defined in claim 1 wherein said abutment means on saidtrigger includes a screw threaded therein and engageable with saidabutment means on said housing.

3. A tool as defined in claim 2 which includes detent means on saidtrigger engageable with said screw to releasably retain said screw inthreadedly adjusted position.

4. A tool as defined in claim 3 wherein said detent means includes acompression spring and ball disposed in a pocket in said trigger, saidball being engageable with serrated head on said screw.

5. A tool as defined in claim 3 wherein said trigger includes a fingeraccommodating portion, said screw being located behind said fingerportion.

1. A portable tool comprising a housing, a variable speed motor in saidhousing and adapted to be connected to a power source, control means forvarying the speed of said motor, a trigger pivoted on said housing andinterconnected with said control means, and movable in a first directionto turn said motor ''''off'''' and in a second direction to turn saidmotor ''''on,'''' said trigger having an outer portion adapted forfinger engagement during operation of said tool and an inner portiongenerally inaccessible to the fingers of an operator during tooloperation, engageable abutment means rigid with said housing and triggerto limit movement of said trigger in said second direction, means onsaid trigger at the inner portion thereof for adjusting said abutmentmeans relative thereto whereby to adjust the range of pivotal movementof said trigger in said second direction and correspondingly the speedof said motor.
 2. A tool as defined in claim 1 wherein said abutmentmeans on said trigger includes a screw threaded therein and engageablewith said abutment means on said housing.
 3. A tool as defined in claim2 which includes detent means on said trigger engageable with said screwto releasably retain said screw in threadedly adjusted position.
 4. Atool as defined in claim 3 wherein said detent means includes acompression spring and ball disposed in a pocket in said trigger, saidball being engageable with serrated head on said screw.
 5. A tool asdefined in claim 3 wherein said trigger includes a finger accommodatingportion, said screw being located behind said finger portion.